John Donne wrote around the 16th century, He was a clergy man and considered a great metaphysical poet. Most of his writings are poetry or sermons. He wrote a great deal about marriage and many of his poems and sermons are about the beauty of physical love within marriage. He has been a long time favorite of mine.
Ayn Rand was Russian and wrote during the early to mid 20th century. She was a self-proclaimed athiest. Her god was the almighty $ and she believed in capitalism beyond all else. She was overbearing and accepted no other viewpoints beyond her own. I think her best book was The Fountainhead, but that is just my opinion. She is very interesting as a writer, but was not considered very likeable as a human being.